Cassini was the son of Jean Dominique Cassini and Genevieve de Laistre. His father was a greatly esteemed astronomer, head of the Paris observatory, an academicien, and active in the cartographical projects of France.

It is clear that Jean Dominique Cassini became wealthy as the head of the observatory.

3. Nationality

Birth: France

Career: France

Death: France

4. Education

Schooling: No University

Began his studies at Family's home in Paris observatory.

Entered the College Mazarin. 1691, defended a thesis in optics under Varignon. Fontenelle wrote that Cassini, at the age of fifteen, dedicated a mathematical thesis to the Duc de Bourgogne. Probably his thesis in optics is meant.

1694, admitted as a student to the Académie des Sciences.

There is no record of any university or standard academic degree.

5. Religion

Affiliation: Catholic (assumed).

6. Scientific Disciplines

Primary: Astronomy, Cartography

Subordinate: Electricity, Physics, Optics

He travelled with his father through Italy, Flanders, the Netherlands, and England making numerous geodesic measurements as well as several astronomical observations.

He presented a new method for the determination of longitudes by means of the eclipses of the stars and planets by the moon.

In 1713 he took the position supporting the hypothesis of the elongation of the terrestrial ellipsoid. In his work, De la grandeur et de la figure de la terre (1722), he presented information confirming his hypothesis. In 1733-34 he undertook the determination of the perpendicular to the meridian of Paris from Saint-Malo to Strasbourg in order to defend his views against those of Desaguliers, Maupertuis, and Poleni.

In astronomy Cassini's primary interests were the study of planets and their satellites, the observation and theory of comets, and the tides. Cassini fought continually to defend the work of his father and to reconcile the facts of observation with the theory of vortices. The improvements of instruments and the appearance of new methods were not used to their full extent by this timid Copernican and convinced Cartesian.

He gave papers to the Academie on electricity, the recoil of firearms, barometers, and burning mirrors.